Season extension has become standard practice among farmers and many home gardeners across the country.  Growing tomatoes in a high tunnel or hoop-house extends the season by providing protection from frost and maintaining warmer temperatures that allow for earlier harvest.  High tunnels and greenhouses also provide a protected growing environment for plants which increases the potential for higher yields and more uniform fruit. Already growing tomatoes in a high tunnel?  High Mowing offers a range of high performance varieties from beefsteak slicers to cherry tomatoes.  Check out our stellar selection of Organic Greenhouse Hybrid Tomato Seeds. Some high tunnels are quite low tech: simple hoop structures covered in clear polyethylene plastic that offer frost protection at the start of the season to allow for earlier planting. Others are more elaborate with greater capacity to control heat and humidity. Regardless of how complicated your high tunnel structure is, at the very least you want to be able to open up and vent. Optimum night time temperatures are between 60 - 65 degrees and optimum daytime temperatures are between 70 - 80 degrees. These temperatures provide for good fruit ripening with no reduction in growth or fruit set.  Be sure to promote good airflow and constant temperatures, and to minimize humidity.  Moisture on the plants, in a high tunnel as in the field, can result in the spread of disease.

Choosing a Greenhouse Variety:

Choose an indeterminate variety that that will produce over a long period of time. The space in your high tunnel is expensive real estate – just think of the time and materials that went into that construction!  You don’t want to plant something that will peter out quickly or produce low yields.  NOTE: One exception to this rule would be a grower with a cropping plan that prioritizes late summer/fall plantings in the high tunnel for fall/winter harvest.  In this case, an early, determinate tomato variety could provide an early, condensed harvest and then leave the space for a later planting of a different crop.
Trials Manager Gwenael Engleskirchen leading a tour of our Greenhouse Tomatoes.
Choose a variety with disease resistance.  Again, your high tunnel is valuable space.  Be sure to plant a variety that will outlast the disease and continue producing, not one that will succumb to disease. Choose a variety that is bred for high tunnel Many field varieties require strong light and low humidity conditions and may not yield as well in a high tunnel.  According to Mississippi State Extension’s Greenhouse Tomato Handbook, a high tunnel has about 20% less light than outdoors, and varieties bred and selected for high tunnel production will perform better in these conditions.  Choose a variety that you or your customers will want to eat.  Although we recognize that most greenhouse varieties can’t hold a candle to the heirlooms in taste and flavor complexity, we do emphasize the importance of flavor in our variety selection. You can grow the prettiest tomato in the world, but will you and your customers want to eat it? We have declined to carry many greenhouse tomatoes that look good but taste bad.  We certainly value performance, but remember that taste buds are important, too.

High Mowing Organic Seeds’ Tomato Varieties Bred for High Tunnel Production

At High Mowing Organic Seeds, we realize that our customers are growing under a wide range of conditions and cultural practices. For this reason, we focus on varieties that are adaptable. All of the tomato varieties highlighted below, in addition to being bred for performance in greenhouse/high tunnel conditions, also perform well in open field conditions. Most – if not all – varieties bred for protected culture are hybrid varieties, including the below varieties.  If you want to grow an open-pollinated variety, we have seen good performance and strong yields from Moskvich, although it was more susceptible to disease.
  • Lola F1: If you’re looking for a greenhouse slicer with flavor, then Lola is your girl. This 7-9 oz red tomato received top flavor ratings in our 2010 trials – and as if that weren’t enough, it is early and high yielding. Lola rated higher in overall vigor and appearance than many of the market standards we also grew that year (Cobra F1, Trust F1 and Buffalo F1). Lola has thinner skin and better texture than most other greenhouse tomatoes and is not as tough.  Resistances: FW (races 1,2), TMV
  • Sakura F1: Sakura is a new introduction this year. This sweet red cherry tomato is very comparable in size and yield to Suzanne. The firm ½ - ¾ oz fruit holds well on the vine, allowing for the harvest of an entire truss for an attractive display. Firm skin makes fruit resistant to cracking, making this variety well adapted to field production.  Resistances: TMV, LM (races 1-5), FW (races 0,1)
  • Suzanne F1: To bite into a Suzanne cherry tomato is to get a burst of candy sweet tartness.  These ½ oz red cherries are delicious and juicy, so it’s no wonder they ranked highest in sweetness and flavor in our 2011 tomato taste test.  Attractive fruit hangs in long trusses, and holds well, though not as well as Sakura. Resistances: FF (races1-5), FW (race 0,1), TMV
  • Toronjina F1: This is another high-ranking tomato for flavor.  It is very eye-catching in combination with Suzanne or Sakura.  These ¾ oz fruit display a bright, beautiful orange color. This excellent organic variety rivals the beloved Sun Gold F1. In addition, this variety showed good resistance to late blight in 2010 when we trialed it in the open field.  Resistances: FF (races 1-5), FW (races 0,1), TMV